1. Field of the Present Invention
The present invention relates to a flexible substrate for the package of a die, and more particularly, to a flexible substrate which can prevent the leads from being peeled off from the bump of the die during the packaging process. Additionally, the flexible substrate can be provided for alignment and positioning of the inner lead bonding processing machine.
2. Description of the Prior Art
In the field of integrated circuit chip packaging, flexible substrate like tape carrier package (TCP) is one of the familiar methods. TCP employs a flexible substrate with a device hole and a plurality of leads as the chip substrate. The structure of the tape carrier package is the most suitable for packaging a semiconductor device with multi-connection terminals into a compact size. Thus, such tape carrier packages are the most widely utilized carrier packages for a semiconductor device for driving a liquid crystal display panel.
The flexible substrate has a plurality of leads. The leads are used to be a connection bonded to bumps of a die, and each of them further formed an electrical connection between the flexible substrate and the die. The bumps on the die are generally gold bumps. Through an inner lead bonding process, the gold bumps are bonded to the leads on the flexible substrate.
The leads of the prior art exhibit a long slim shape, and the width of each lead is less than that of a bump. When the number of leads is increased, the width of the leads should be reduced to prevent the mutual interaction of the leads and to consider other aspects of the inner lead bonding process. Accordingly, in a multiple leads packaging process, because the leads are too thin, the adhesive force between the leads and the bumps of the die will be too weak and will further cause the leads to be peeled off from the bumps. Especially, the leads at the corner often get peeled off from the bumps because of the shear force of the thermal-expanded flexible substrate, further resulting in electrical disconnection.
Accordingly, the present invention provides a flexible substrate for the packaging of a die. The flexible substrate, in accordance with the present invention, can solve the problem of the leads being peeled off from the bumps described above. Furthermore, the flexible substrate can be provided for the alignment and positioning of the inner lead bonding processing machine.